1. Field of the Invention
The present invention relates to a mechanism for supplying a lubricating oil to bearings, etc. in a swash plate type compressor.
2. Description of the Related Art
The prior mechanism for supplying a lubricating oil to bearings, etc. in a swash plate type compressor is explained later in detail, with reference to an attached drawing.
In the prior mechanism, a passage for an lubricating oil must be formed in a drive shaft. The drive shaft, however, is formed of a very stiff material, because any distortion thereof at a high rotational speed must be prevented. Also the passage is long and has a small diameter, and accordingly, machining of the passage is difficult, for example, the drill bit is often broken during the machining, and removing burrs and washing the passage is also difficult. Therefore, a mass production of this passage is practically very difficult. Furthermore, it is difficult to reduce a diameter of the drive shaft while maintaining the strength thereof, because the passage for the lubricating oil is formed therein. Further, a required amount of the lubricating oil cannot be supplied to the upper portion of the compressor when the drive shaft is rotated at a low speed, i.e, less than 700 r.p.m., because the oil is fed from an outlet port on the drive shaft by centrifugal force.